A first class of optical medium, such as, for example, CD-RW, DVD-RW, as well as others, is fully formatted (also known as “de-icing”), before random read and random write operations can be performed throughout the optical medium. As a result, a considerable amount of time is spent, during the formatting, before user data can be transferred onto the optical medium. Depending on a speed of an optical drive or an optical medium, the formatting may take anywhere from 20-50 minutes. During the 20-50 minutes of the formatting, the optical medium cannot be used by a user.
A second class of optical medium, such as, for example, CD-Mount Rainier ReWritable (CD-MRW) and DVD+RW, as well as others, is available for user access before an optical medium is completely formatted, or de-iced. The second class of optical medium is designed to be capable of supporting background formatting, or de-icing, while allowing random user access. An optical drive, itself, formats the optical medium of the second class in the background. Background formatting and random user access of the second class of optical media by the optical drive is possible because of information that is preserved on the optical medium. For example, a bitmap of all recorded error correction code (ECC) blocks, as well other information, may be preserved on the optical medium.